The design and performance of potentiostats

Abstract The factors which affect the design of potentiostats are discussed with particular emphasis of the following points: the accuracy to which a desired potential can be maintained; the stabilization of the regulator and the effect of the cell design on this stabilization; the frequency range over which measurements can be made; the manner in which the characteristics of the working electrode determine the design of the output stage. The effect of some of these factors on the time dependence of the error signal is calculated using lumped parameter approximations for the circuits in the cell and regulator. The way in which the time response can be improved is indicated. Circuit details are given for two designs of potentiostats used in these laboratories which are suitable for measurements at very short times. The design of a pulse generator which provides a number of pulse profiles frequently used in experiments at constant potential is also given.